Hyaluronan receptors (HARs)

Hyaluronan receptors, including CD44, RHAMM (HMMR), and HARE (STAB2), are a diverse group of proteins that mediate the biological effects of hyaluronan (HA), a primary glycosaminoglycan found in the extracellular matrix and synovial fluid (Citations: UniProt P16070, PubMed: 25861727). These receptors are essential for maintaining the structural integrity and lubrication of synovial joints, where they regulate cell-matrix interactions and inflammatory responses. In pathological conditions such as osteoarthritis, the degradation of the HA-rich matrix and altered receptor signaling contribute to joint pain and cartilage degeneration (Citations: StatPearls - Osteoarthritis, PubMed: 12065013). Therapeutic strategies often involve viscosupplementation, where exogenous HA is injected into the joint to coat synovial surfaces and interact with these receptors to restore mechanical function and dampen inflammation (Citations: FDA - Hyaluronan Products). Beyond orthopedics, CD44 is frequently overexpressed in various cancers, where it promotes tumor cell migration and chemoresistance, making it a significant target for oncology drug delivery and diagnostic imaging (Citations: PubMed: 30659080). The target description provided is considered 'incorrect' as a canonical name because it combines a functional group of receptors with a physical anatomical location (synovial surfaces) rather than identifying a single molecular entity.

Other names

CD44 antigenReceptor for Hyaluronan-Mediated Motility (RHAMM)Hyaluronan receptor for endocytosis (HARE)Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1)Stabilin-2HMMRCD44Hyaladherins

Binding and activation of CD44 and RHAMM to modulate intracellular signaling pathways (e.g., MAPK, PI3K) and providing mechanical lubrication and viscoelastic support to synovial surfaces.